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class="sidebar-resizer"></div><main><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><h1><div class="sub-heading">indexmap/</div>lib.rs</h1><rustdoc-toolbar></rustdoc-toolbar></div><div class="example-wrap"><div data-nosnippet><pre class="src-line-numbers"> <a href="#1" id="1">1</a> <a href="#2" id="2">2</a> <a href="#3" id="3">3</a> <a href="#4" id="4">4</a> <a href="#5" id="5">5</a> <a href="#6" id="6">6</a> <a href="#7" id="7">7</a> <a href="#8" id="8">8</a> <a href="#9" id="9">9</a> <a href="#10" id="10">10</a> <a href="#11" id="11">11</a> <a href="#12" id="12">12</a> <a href="#13" id="13">13</a> <a href="#14" id="14">14</a> <a href="#15" id="15">15</a> <a href="#16" id="16">16</a> <a href="#17" id="17">17</a> <a href="#18" id="18">18</a> <a href="#19" id="19">19</a> <a href="#20" id="20">20</a> <a href="#21" id="21">21</a> <a href="#22" id="22">22</a> <a href="#23" id="23">23</a> <a href="#24" id="24">24</a> <a href="#25" 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#![warn(rust_2018_idioms)] #![no_std] </span><span class="doccomment">//! [`IndexMap`] is a hash table where the iteration order of the key-value //! pairs is independent of the hash values of the keys. //! //! [`IndexSet`] is a corresponding hash set using the same implementation and //! with similar properties. //! //! ### Highlights //! //! [`IndexMap`] and [`IndexSet`] are drop-in compatible with the std `HashMap` //! and `HashSet`, but they also have some features of note: //! //! - The ordering semantics (see their documentation for details) //! - Sorting methods and the [`.pop()`][IndexMap::pop] methods. //! - The [`Equivalent`] trait, which offers more flexible equality definitions //! between borrowed and owned versions of keys. //! - The [`MutableKeys`][map::MutableKeys] trait, which gives opt-in mutable //! access to map keys, and [`MutableValues`][set::MutableValues] for sets. //! //! ### Feature Flags //! //! To reduce the amount of compiled code in the crate by default, certain //! features are gated behind [feature flags]. These allow you to opt in to (or //! out of) functionality. Below is a list of the features available in this //! crate. //! //! * `std`: Enables features which require the Rust standard library. For more //! information see the section on [`no_std`]. //! * `rayon`: Enables parallel iteration and other parallel methods. //! * `serde`: Adds implementations for [`Serialize`] and [`Deserialize`] //! to [`IndexMap`] and [`IndexSet`]. Alternative implementations for //! (de)serializing [`IndexMap`] as an ordered sequence are available in the //! [`map::serde_seq`] module. //! * `borsh`: Adds implementations for [`BorshSerialize`] and [`BorshDeserialize`] //! to [`IndexMap`] and [`IndexSet`]. //! * `arbitrary`: Adds implementations for the [`arbitrary::Arbitrary`] trait //! to [`IndexMap`] and [`IndexSet`]. //! * `quickcheck`: Adds implementations for the [`quickcheck::Arbitrary`] trait //! to [`IndexMap`] and [`IndexSet`]. //! //! _Note: only the `std` feature is enabled by default._ //! //! [feature flags]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-features-section //! [`no_std`]: #no-standard-library-targets //! [`Serialize`]: `::serde::Serialize` //! [`Deserialize`]: `::serde::Deserialize` //! [`BorshSerialize`]: `::borsh::BorshSerialize` //! [`BorshDeserialize`]: `::borsh::BorshDeserialize` //! [`arbitrary::Arbitrary`]: `::arbitrary::Arbitrary` //! [`quickcheck::Arbitrary`]: `::quickcheck::Arbitrary` //! //! ### Alternate Hashers //! //! [`IndexMap`] and [`IndexSet`] have a default hasher type //! [`S = RandomState`][std::collections::hash_map::RandomState], //! just like the standard `HashMap` and `HashSet`, which is resistant to //! HashDoS attacks but not the most performant. Type aliases can make it easier //! to use alternate hashers: //! //! ``` //! use fnv::FnvBuildHasher; //! use fxhash::FxBuildHasher; //! use indexmap::{IndexMap, IndexSet}; //! //! type FnvIndexMap<K, V> = IndexMap<K, V, FnvBuildHasher>; //! type FnvIndexSet<T> = IndexSet<T, FnvBuildHasher>; //! //! type FxIndexMap<K, V> = IndexMap<K, V, FxBuildHasher>; //! type FxIndexSet<T> = IndexSet<T, FxBuildHasher>; //! //! let std: IndexSet<i32> = (0..100).collect(); //! let fnv: FnvIndexSet<i32> = (0..100).collect(); //! let fx: FxIndexSet<i32> = (0..100).collect(); //! assert_eq!(std, fnv); //! assert_eq!(std, fx); //! ``` //! //! ### Rust Version //! //! This version of indexmap requires Rust 1.63 or later. //! //! The indexmap 2.x release series will use a carefully considered version //! upgrade policy, where in a later 2.x version, we will raise the minimum //! required Rust version. //! //! ## No Standard Library Targets //! //! This crate supports being built without `std`, requiring `alloc` instead. //! This is chosen by disabling the default "std" cargo feature, by adding //! `default-features = false` to your dependency specification. //! //! - Creating maps and sets using [`new`][IndexMap::new] and //! [`with_capacity`][IndexMap::with_capacity] is unavailable without `std`. //! Use methods [`IndexMap::default`], [`with_hasher`][IndexMap::with_hasher], //! [`with_capacity_and_hasher`][IndexMap::with_capacity_and_hasher] instead. //! A no-std compatible hasher will be needed as well, for example //! from the crate `twox-hash`. //! - Macros [`indexmap!`] and [`indexset!`] are unavailable without `std`. </span><span class="attr">#![cfg_attr(docsrs, feature(doc_cfg))] </span><span class="kw">extern crate </span>alloc; <span class="attr">#[cfg(feature = <span class="string">"std"</span>)] #[macro_use] </span><span class="kw">extern crate </span>std; <span class="kw">use </span>alloc::vec::{<span class="self">self</span>, Vec}; <span class="kw">mod </span>arbitrary; <span class="attr">#[macro_use] </span><span class="kw">mod </span>macros; <span class="attr">#[cfg(feature = <span class="string">"borsh"</span>)] </span><span class="kw">mod </span>borsh; <span class="attr">#[cfg(feature = <span class="string">"serde"</span>)] </span><span class="kw">mod </span>serde; <span class="kw">mod </span>util; <span class="kw">pub mod </span>map; <span class="kw">pub mod </span>set; <span class="comment">// Placed after `map` and `set` so new `rayon` methods on the types // are documented after the "normal" methods. </span><span class="attr">#[cfg(feature = <span class="string">"rayon"</span>)] </span><span class="kw">mod </span>rayon; <span class="attr">#[cfg(feature = <span class="string">"rustc-rayon"</span>)] </span><span class="kw">mod </span>rustc; <span class="kw">pub use </span><span class="kw">crate</span>::map::IndexMap; <span class="kw">pub use </span><span class="kw">crate</span>::set::IndexSet; <span class="kw">pub use </span>equivalent::Equivalent; <span class="comment">// shared private items </span><span class="doccomment">/// Hash value newtype. Not larger than usize, since anything larger /// isn't used for selecting position anyway. </span><span class="attr">#[derive(Clone, Copy, Debug, PartialEq)] </span><span class="kw">struct </span>HashValue(usize); <span class="kw">impl </span>HashValue { <span class="attr">#[inline(always)] </span><span class="kw">fn </span>get(<span class="self">self</span>) -> u64 { <span class="self">self</span>.<span class="number">0 </span><span class="kw">as </span>u64 } } <span class="attr">#[derive(Copy, Debug)] </span><span class="kw">struct </span>Bucket<K, V> { hash: HashValue, key: K, value: V, } <span class="kw">impl</span><K, V> Clone <span class="kw">for </span>Bucket<K, V> <span class="kw">where </span>K: Clone, V: Clone, { <span class="kw">fn </span>clone(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="self">Self </span>{ Bucket { hash: <span class="self">self</span>.hash, key: <span class="self">self</span>.key.clone(), value: <span class="self">self</span>.value.clone(), } } <span class="kw">fn </span>clone_from(<span class="kw-2">&mut </span><span class="self">self</span>, other: <span class="kw-2">&</span><span class="self">Self</span>) { <span class="self">self</span>.hash = other.hash; <span class="self">self</span>.key.clone_from(<span class="kw-2">&</span>other.key); <span class="self">self</span>.value.clone_from(<span class="kw-2">&</span>other.value); } } <span class="kw">impl</span><K, V> Bucket<K, V> { <span class="comment">// field accessors -- used for `f` instead of closures in `.map(f)` </span><span class="kw">fn </span>key_ref(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>K { <span class="kw-2">&</span><span class="self">self</span>.key } <span class="kw">fn </span>value_ref(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>V { <span class="kw-2">&</span><span class="self">self</span>.value } <span class="kw">fn </span>value_mut(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="kw-2">&mut </span>V { <span class="kw-2">&mut </span><span class="self">self</span>.value } <span class="kw">fn </span>key(<span class="self">self</span>) -> K { <span class="self">self</span>.key } <span class="kw">fn </span>value(<span class="self">self</span>) -> V { <span class="self">self</span>.value } <span class="kw">fn </span>key_value(<span class="self">self</span>) -> (K, V) { (<span class="self">self</span>.key, <span class="self">self</span>.value) } <span class="kw">fn </span>refs(<span class="kw-2">&</span><span class="self">self</span>) -> (<span class="kw-2">&</span>K, <span class="kw-2">&</span>V) { (<span class="kw-2">&</span><span class="self">self</span>.key, <span class="kw-2">&</span><span class="self">self</span>.value) } <span class="kw">fn </span>ref_mut(<span class="kw-2">&mut </span><span class="self">self</span>) -> (<span class="kw-2">&</span>K, <span class="kw-2">&mut </span>V) { (<span class="kw-2">&</span><span class="self">self</span>.key, <span class="kw-2">&mut </span><span class="self">self</span>.value) } <span class="kw">fn </span>muts(<span class="kw-2">&mut </span><span class="self">self</span>) -> (<span class="kw-2">&mut </span>K, <span class="kw-2">&mut </span>V) { (<span class="kw-2">&mut </span><span class="self">self</span>.key, <span class="kw-2">&mut </span><span class="self">self</span>.value) } } <span class="kw">trait </span>Entries { <span class="kw">type </span>Entry; <span class="kw">fn </span>into_entries(<span class="self">self</span>) -> Vec<<span class="self">Self</span>::Entry>; <span class="kw">fn </span>as_entries(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[<span class="self">Self</span>::Entry]; <span class="kw">fn </span>as_entries_mut(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="kw-2">&mut </span>[<span class="self">Self</span>::Entry]; <span class="kw">fn </span>with_entries<F>(<span class="kw-2">&mut </span><span class="self">self</span>, f: F) <span class="kw">where </span>F: FnOnce(<span class="kw-2">&mut </span>[<span class="self">Self</span>::Entry]); } <span class="doccomment">/// The error type for [`try_reserve`][IndexMap::try_reserve] methods. </span><span class="attr">#[derive(Clone, PartialEq, Eq, Debug)] </span><span class="kw">pub struct </span>TryReserveError { kind: TryReserveErrorKind, } <span class="attr">#[derive(Clone, PartialEq, Eq, Debug)] </span><span class="kw">enum </span>TryReserveErrorKind { <span class="comment">// The standard library's kind is currently opaque to us, otherwise we could unify this. </span>Std(alloc::collections::TryReserveError), CapacityOverflow, AllocError { layout: alloc::alloc::Layout }, } <span class="comment">// These are not `From` so we don't expose them in our public API. </span><span class="kw">impl </span>TryReserveError { <span class="kw">fn </span>from_alloc(error: alloc::collections::TryReserveError) -> <span class="self">Self </span>{ <span class="self">Self </span>{ kind: TryReserveErrorKind::Std(error), } } <span class="kw">fn </span>from_hashbrown(error: hashbrown::TryReserveError) -> <span class="self">Self </span>{ <span class="self">Self </span>{ kind: <span class="kw">match </span>error { hashbrown::TryReserveError::CapacityOverflow => { TryReserveErrorKind::CapacityOverflow } hashbrown::TryReserveError::AllocError { layout } => { TryReserveErrorKind::AllocError { layout } } }, } } } <span class="kw">impl </span>core::fmt::Display <span class="kw">for </span>TryReserveError { <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, f: <span class="kw-2">&mut </span>core::fmt::Formatter<<span class="lifetime">'_</span>>) -> core::fmt::Result { <span class="kw">let </span>reason = <span class="kw">match </span><span class="kw-2">&</span><span class="self">self</span>.kind { TryReserveErrorKind::Std(e) => <span class="kw">return </span>core::fmt::Display::fmt(e, f), TryReserveErrorKind::CapacityOverflow => { <span class="string">" because the computed capacity exceeded the collection's maximum" </span>} TryReserveErrorKind::AllocError { .. } => { <span class="string">" because the memory allocator returned an error" </span>} }; f.write_str(<span class="string">"memory allocation failed"</span>)<span class="question-mark">?</span>; f.write_str(reason) } } <span class="attr">#[cfg(feature = <span class="string">"std"</span>)] #[cfg_attr(docsrs, doc(cfg(feature = <span class="string">"std"</span>)))] </span><span class="kw">impl </span>std::error::Error <span class="kw">for </span>TryReserveError {} </code></pre></div></section></main></body></html>